Just a quick question.... on the Lehman dough calculator, it mentions that extra virgin olive oil is not advised. Is that simply due to the cost and that you can use a cheaper olive oil or other oil, or is there something more to it then that?

I was the one who added that language to the tool at the time it was created by Boy Hits Car and me. The issue was not one of the undesirability of extra virgin olive oil, but mainly its cost and the availability of lower cost alternatives, especially for a commercial operation. See, for example: